This is the second time this has happened?!?!?!
Anyone know what the heck this is?
It happened after washing and the last time I believe it happened after washing too, but not 100%
To me, it sounds like its purging air from a valve. Its not a tire leak.
More videos below


ANYONE!!!!

 

This is going to sound like I'm making this up but I washed my truck this morning and then drove home. When I got out I heard a hissing noise like air escaping and thought I had a tire or tire stem leaking on the front drivers side so I did the soap test on the tire and stem. No leak found and the hissing stopped no air was lost. I don't have a clue what it was. Never heard it before.

 

HVAC equalizing?

 

I have no idea.....
Here's the 4 videos I took with different sounds....

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It's not your fan is it? I know it's off but if it's windy could it be turning slowly? It definitely sounds like something spinning slowly that may have some residual moisture causing that noise.

No clue though, just guessing.

 

Nope...The truck is off, doors locked, no wind at all.
Started truck and could not hear whistle, not sure if engine noise was masking the sound. But when I turned it off it started making the sound again.
Did not have the AC on today.
It eventually goes away after 10-15 minutes

 

Ya know...my other car made that noise once. It wasn't the EXACT same noise but similar...it ended up being the throttle body. I took the intake snorkle off and the ETB was actually vibrating back and forth. I unhooked the battery, came back and hour later....it never did it again. It was like the actuator didn't know what to do. Again, just a guess. I'd bet though that it's one of the electronic pumps or something like the ETB. Where is it loudest?

 

 

Battery control module, mine did it only when I had the battery unhooked. Freaked me out. Hooked it back up and it was quite immediately. Don't know how it relates to your situation other than I heard it one with my battery unhooked. My research was bcm discharging

 

Should have bought the EcoBoost man. Ha ha. Just kidding. Hope you resolve the issue, but wanted to ask you if your grille is stock. Haven't seen it before, and it looks awesome. Very aggressive. Good job .